Thunder Bay – Weather – It might feel a bit more like October this morning, likely gloves and a jacket are needed.

As we approach the final weekend of August, Thunder Bay is waking up to a cool and foggy morning with a seasonal shift in the air. While the temperature is a crisp 3°C early today, warmer weather is on the horizon.

Fog patches are set to clear, making way for a sun-filled afternoon and a warm, summery weekend ahead.

Today’s Weather Overview

Current Conditions

As of 7:49 AM EDT, Thunder Bay is experiencing fog patches with full saturation in the air—humidity is at 100%. The temperature is holding steady at 3.2°C, with an identical dew point indicating a very damp start to the day. Winds are light, coming from the west-southwest at 6 km/h. Barometric pressure sits at 102.4 kPa and is falling, signaling potential shifts in atmospheric conditions later today.

Visibility remains strong at 24 km, and as the morning progresses, the fog is expected to dissipate. Sunshine will dominate by midday, with temperatures climbing to a pleasant high of 16°C. The UV index will reach 6, categorized as high, so sun protection is recommended for those spending time outdoors.

Weekend Extended Forecast

Expected Conditions

Saturday, August 30

• Day: A beautiful day is ahead with a mix of sun and cloud, and any remaining fog patches will clear by morning. Temperatures will surge to a high of 25°C, and the humidex will make it feel like 28°C, giving a final taste of summer.

• Night: Skies will remain clear through the evening with an overnight low of 12°C.

Sunday, August 31

• Day: A classic summer day in late August — sunny skies and a high of 24°C.

• Night: Clear skies persist with a cool low of 11°C.

Monday, September 1 (Labour Day)

• Day: A mix of sun and cloud continues the pleasant weather trend with temperatures climbing to a high of 25°C.

• Night: Cloudy periods will move in late, with a mild low of 13°C.

Wardrobe Recommendations

Today’s chilly start calls for layers—think a warm hoodie or light jacket in the morning, especially if you’re heading out early. As temperatures climb to the mid-teens later today, a transition to lighter attire like long-sleeve shirts or light sweaters will be comfortable.

For the weekend:

• Saturday through Monday will bring much warmer conditions. T-shirts, shorts, and breathable fabrics are ideal during the day. Don’t forget sunscreen and sunglasses, especially with a high UV index.

• Bring a light jacket or sweater for cooler evenings, particularly if you’re planning to be outdoors after sunset.

Weather Trivia

Did You Know?
Thunder Bay holds the record for Ontario’s highest humidex ever recorded in August, with a humidex of 42.5°C observed on August 1, 1988. While this weekend’s humidex of 28°C isn’t close to that record, it’s a reminder that late summer can still pack in some heat!